One vertex per element, one color per generator, with an edge from x to x·s.
(2,6)(3,4)(7,8)(9,10,13,18,29,24,35,22,14,19,30,17,15,11,20,23)(12,25,27,32,40,21,36,39,26,16,31,33,28,37,34,38)(1,2)(3,6)(4,8)(5,7)(9,11)(10,15)(12,21)(13,18)(14,24)(16,28)(17,30)(19,29)(20,22)(23,35)(25,40)(26,37)(27,33)(31,32)(34,38)(36,39) involution — undirected(1,3,5,4)(2,6,7,8)(9,12,14,26)(10,16,19,25)(11,21,24,37)(13,27,30,31)(15,28,29,40)(17,32,18,33)(20,34,35,36)(22,38,23,39)(12,26)(16,25)(21,37)(27,31)(28,40)(32,33)(34,36)(38,39) involution — undirectedA Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.